1. Field of the Invention
The present invention generally involves the field of technology involving devices for pivotally mounting a door to a cabinet for closing an opening formed in a wall of the cabinet. In particular, the invention relates to an improved hinge assembly for mounting a door on a refrigerator cabinet wherein the door is provided with a sealing gasket that is compressed around the peripheral surface of the cabinet opening.
2. Description of the Prior Art
The food storage compartment of a conventional refrigerator cabinet is provided with a door which is mounted to the cabinet for pivotal movement about a vertical hinge axis that is defined by a pair of spaced hinges attached to corresponding edge portions of the cabinet and door. The inside surface of the door is provided with a circumferential gasket for sealing engagement against a corresponding peripheral surface around the cabinet opening to prevent energy loss when the door is closed. The pivotal movement about the hinge axis during closing of the door necessarily creates a wiping of the gasket against portions of the peripheral surface around the cabinet opening, particularly in the region along the corresponding edge portions of the cabinet and door. This situation prevents the uniform compression of the entire gasket and accelerates its wear.
The prior art has attempted to overcome these problems by providing a refrigerator hinge structure which, in automatic response to pivoting the door open about its hinge axis, causes the hinged edge of the door to be shifted in a direction transverse to the front wall of the cabinet. This permits a more uniform compression of the gasket around the cabinet opening during closing of the door. This arrangement serves the further purpose of permitting the cabinet to be installed in a corner with the side wall of the cabinet disposed adjacent a wall of the room projecting beyond the front of the refrigerator since the shifting of the hinged edge permits the door to be swung to a full right angled position without interference from the projecting wall.
Another problem arises when the inside surface of a refrigerator door within the perimeter of the gasket is provided with a door "dike" system. The door dike is in the form of a molded projection which extends outwardly from the inner surface of the door for defining shelf and storage within its perimeter. The dike extends inwardly into the refrigerated compartment formed by the food cabinet liner when the door is in its fully closed position. Since a conventional pivotal hinge assembly for a refrigerator requires that the door open and close about a fixed pivotal axis, it is required to radius or form the peripheral wall region of the dike inwardly in order to permit the door to open and close because of the projecting dike. This necessarily creates a large clearance between the peripheral wall region of the dike and the opposed adjacent portions of the food liner, a situation which results in energy loss if the door gasket is of insufficient construction or is not uniformly compressed against the peripheral surface of the cabinet opening.
In addition to the foregoing, it is also generally known to mount a door for pivotal movement about a vertical hinge axis wherein opening of the door requires an initial shifting of the hinge axis in one or more directions prior to permitting the door to pivot about the hinge axis. This arrangement is commonly found in hinge structures for mounting aircraft doors wherein, before it is permitted to pivot about its hinge axis, the door must first be displaced from a position in which the hinge axis makes an acute angle with the horizontal plane of the airframe to a position in which it is substantially perpendicular to the horizontal plane.